焦油深加工（Tar deep processing）.docVIP

焦油深加工（Tar deep processing） Coal tar and deep processing data Section 1 formation and properties of coal tar Coal tar is a black or dark brown sticky liquid produced by carbonization of coal, which is called tar. Coal tar can be divided into low temperature tar and high temperature tar according to different temperature of carbonization. Low temperature carbonization of low relative density, the composition of alkanes, alkenes and aromatic hydrocarbons accounted for about 50% of the total phenolic content of up to about 30%, mainly for the rest of pyridine bases containing nitrogen and sulfur compounds and colloidal substance in lignite tar also contains a lot of paraffin. High temperature tar is the product of two decomposition of low temperature tar at high temperature. Tar obtained in modern coking production belongs to high temperature tar, and is mainly discussed. High temperature tar is a complex mixture of aromatic hydrocarbons. Its yield, quality and composition depend on the nature of coking coal blending and the operation conditions during the coking process. The coking coal material is light in age, high in volatile content, low in softening temperature, long in the gum state, and high in tar yield. In coke oven operation, furnace wall temperature increases and top space temperature increased, will lead to the tar pyrolysis, the tar yield decreases in the high temperature tar product content of anthracene, naphthalene, asphalt and free carbon increases, density increases, reduce the content of phenolic and neutral oil. The lack of coal loading in the carbonization chamber and the over heating of Coke will increase the furnace space temperature and the furnace wall temperature. Moreover, the yield and composition of the tar are also affected by the pressure system of the coke oven. Normally, the yield (yield) of coal tar is about 3% - 4% of that of coal. Coal tar is estimated to contain tens of thousands of kinds of organic substances, for the most part, wi